A 6-year-old girl is brought to the physician by her mother for a 1-day history of a painful left hip. She recently recovered from an upper respiratory tract viral infection. Temperature is 100 F. Physical examination shows no redness or swelling of the hip. She can bear weight. Leukocytes are 10,000/μL. Which of the following is the most likely explanation for these findings?
Acute inflammatory reaction of synovial lining
Avascular necrosis
Bacterial infection
Disruption of capital femoral epiphyseal plate
Poorly developed acetabulum inflamed by viral antigen
